A number of injector-actuated syringes and powered injectors for use in medical procedures such as angiography, computed tomography, ultrasound and NMRIMRI have been developed. U.S. Pat. No. 4,006,736, for example, discloses an injector and syringe for injecting fluid into the vascular system of a human being or an animal. Typically, such injectors comprise drive members such as pistons that connect to a syringe plunger. For example, U.S. Pat. No. 4,677,980, the disclosure of which is incorporated herein by reference, discloses an angiographic injector and syringe wherein the drive member of the injector can be connected to, or disconnected from, the syringe plunger at any point along the travel path of the plunger via a releasable mechanism. A front-loading syringe and injector system is also disclosed in U.S. Pat. No. 5,383,858, the disclosure of which is incorporated herein by reference.
As discussed in U.S. Pat. No. 5,383,858, a syringe used with a front-loading injector preferably includes a readily releasable mounting mechanism for securing the syringe to the front wall of the injector. The use of specifically designed mounting mechanisms, however, prevents the use of syringes of other various types with front-loading injectors. Such syringes may, for example, include a syringe body, a plunger reciprocally mounted therein, and a plunger extension for transfer of force to the plunger.
U.S. Pat. No. 5,520,653, the disclosure of which is incorporated herein by reference, discloses several adapters designed to allow the use of various syringes with a front-loading injector. In one embodiment, the adapter of U.S. Pat. No. 5,520,653 includes a syringe carrier having a front end, a rear end, and syringe retaining channel located between the carrier front and rear ends for engaging at least a portion of the syringe flange. Mounting flanges near the rearward end of the carrier lo releasably mount the carrier in a desired position relative to the front wall of the injector. The adapter of U.S. Pat. No. 5,520,653 further includes a follower reciprocally mounted within the carrier. The follower has a front end that engages the syringe plunger extension when the syringe is installed in the carrier. A drive head opening in the carrier communicates with a pair of drive head slots positioned near the rear end of the follower for releasably mounting the follower in a desired position relative to the drive head of the injector.
Although U.S. Pat. No. 5,520,653 is a substantial improvement in the art, it remains desirable to develop improved adapters for use with syringes of various types to permit use of such syringes with front-loading injectors.